The present invention relates to an improved brush assembly and method for obtaining endocervical tissue samples.
Since the introduction of cervical cytology screening by George Papanicolaou in 1940, the Papanicolaou smear has become a well-known procedure for the early detection of abnormalities of the cervical epithelium which has led to the reduction of mortality from carcinoma of the uterine cervix.
A number of devices have been developed to collect samples from the cervix. These devices have included: cotton swabs, applicators, wooden spatulas and endocervical sample collecting brushes. However, a broad range of false negative results from the Papanicolaou smear have been reported due, in part, to the sampling devices used and the method in which these devices have been used.
Although endocervical sample collecting brushes and endometrium sample collecting brushes are well known and popular among practitioners, there are many disadvantages associated with the present brushes. One of the disadvantages is that none have adequately addressed the need to protect health care workers from infection or transmission of the human immunodeficiency virus.
One of the commonly used brush assemblies is comprised of an elongated handle to which is attached a rectangular or cone-shaped brush head. During use, the brush assembly is inserted inside the vagina to place the brush at the opening of the endocervical canal and is then rotated one or more full turns to scrape off tissue material. Then the brush assembly is removed, and the tissue material is deposited onto a microscope slide for examination.
A disadvantage associated with this type of brush assembly is that its tip comprises a helically-wound, thin wire which extends beyond the bristles. Upon insertion into the vagina and endocervical canal, the tip may contact the walls of the vagina and endocervical canal. This contact causes patient discomfort and increases the risk of potential injury to the vagina and endocervical canal.
A second disadvantage is the shape of the handle which is generally cylindrical and typically includes a smooth outer surface. Since the user grasps the handle while wearing latex examination gloves dusted with corn starch, there is a tendency, due to the handle's cylindrical shape and smooth outer surface, for the user's thumb or finger to slip off the handle while the brush is manipulated and rotated during use.
As indicated above, the brush assembly is rotated one or more full turns when collecting tissue material and also when depositing the tissue onto the microscope slide glass for examination. Another disadvantage associated with available brush assemblies is the inability to accurately determine the number of times the brush has been turned.
Another disadvantage associated with this type of brush assembly is its size, and more particularly, the length of the handle. A typical brush assembly is approximately 17-20 cm in length and thus requires a package of approximately the same length. The need for such a lengthy package unnecessarily increases manufacturing costs and the amount of space which such a brush occupies in a doctor's or hospital's already crowded medical supply cabinet.
Yet another disadvantage associated with this type of brush assembly is the tendency of the brush to come into contact with the walls of the vagina and cervical canal, both during insertion and removal, thus contaminating the tissue sample collected from the cervix.
Yet another disadvantage associated with this type of brush assembly is that it requires the use of a speculum to enlarge the vaginal opening and allow insertion and removal of the brush assembly without contacting the walls of the vagina, thus preventing contamination of the brush with unwanted tissue. A disadvantage associated with the use of a speculum is patient discomfort during use thereof.
Yet another disadvantage associated with this type of brush assembly is that, following removal from its protective packaging, the brush is susceptible to contamination through handling and manipulation both prior to and during use, and further, is not adapted for aseptic disposal.